It is taught to everybody at a very young age that there are five senses: sight, smell, touch, taste, and hearing. Eyesight is arguably the most powerful of all the senses. And it can be hard to read that 24 point font on a sign 40 feet away telling drivers about the nearest gas station. Your eyes are always at work, even in your sleep.
While sleeping the eyes reach a stage called rapid eye movement (REM). REM cycles happen multiple times during everyone’s sleep. They are moments of increased brain activity, and the eyes move at rapid rates. These sleep patterns help neurologists study the brain and how it functions during sleep. Optometric studies show that the brain actually “deletes” the movement of your eyes because the 45 minutes of blur daily is essentially useless. This phenomenon is scientifically referred to as saccadic masking.
Computers and technological screens give off a blue light that is still being studied to prove how harmful it is to the eyes. During day time it can be beneficial to energy levels and mood, but during the night it can lead to a rise in serotonin, keeping people awake. Reading while lacking focus and the ability to stay awake can lead to eye-straining. Eye strain can lead to dry eyes, which is very bad for contact wearers.
Contact wearers want to clean their contacts regularly to prevent infection\; however, it doesn’t always end like that every night. Often times people may forget to take their contacts out, and they sleep with them in leading to a larger production of eye discharge. Eye discharge is more commonly referred to as eye boogers/crust. The discharge is completely harmless, and it is used to lubricate, clean, and wet the eyes after a long day.
Leaving contacts in for too long can lead to conjunctivitis. It is a highly contagious infection that is described as the inflammation of the conjunctiva. It is just a thin membrane on the inside of the eyelids and whites of the eyes. Conjunctivitis, or pink eye, is easily treatable with prescription eye drops\; however, if it goes untreated for too long it can be spread to more people and lead to discomfort. Large amounts of discharge are produced during the cycle of infection.
For everyone, maintain good hygiene with your eyes and don’t stare at a screen for 16 hours a day. Maintaining healthy eyes can prevent serious complications and preserve one of your most important senses.

References
Dodge, R. (1900). Visual perception during eye movement. Psychological Review, 7(5), 454–465. https://doi.org/10.1037/h0067215

Harvard Health Publishing. “Blue Light Has a Dark Side.” Harvard Health, www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side?scrlybrkr=29a125e3.

Dahl, Andrew A. “Eye Strain Treatment, Causes, Symptoms, Relief & Prevention.” MedicineNet, www.medicinenet.com/eye_strain/article.htm.